details page is redirecting to catalog.php

<?php 

include("inc/data.php");
include("inc/functions.php");




if (isset($_GET["id"])) {
  $id = $_Get["id"];
  if (isset($catalog[$id])); {
      $item = $catalog[$id];
  }
}


if (!isset($item)) {
    header("location:catalog.php");
    exit;  
}

$pageTitle = $item["title"];
$section = null;

include("inc/header.php"); ?>

<div class="section page">

  <div class="wrapper">

      <div class="media-picture">
          <span>
            <img src="<?php echo $item["img"]; ?>" alt="<?php echo $item["title"]; ?>" />
          </span>

      </div> 

    <div class="media-details">

        <h1><?php echo $item["title"]; ?></h1>
        <table>       
          <tr>
                <th>Category</th>
                <td><?php echo $item["catagory"]; ?></td>
          </tr>
          <tr>
                <th>Genre</th>
                <td><?php echo $item["genre"]; ?></td>
          </tr>
          <tr>
                <th>Format</th>
                <td><?php echo $item["format"]; ?></td>
          </tr>
          <tr>
                <th>Year</th>
                <td><?php echo $item["year"]; ?></td>
          </tr>
              <?php if (strtolower($item["category"]) == "books") { ?>
          <tr>
                <th>Authors</th>
                <td><?php echo implode(", ",$item["authors"]); ?></td>
          </tr>
          <tr>
                <th>Publisher</th>
                <td><?php echo $item["publisher"]; ?></td>
          </tr>
          <tr>
                <th>ISBN</th>
                <td><?php echo $item["isbn"]; ?></td>
          </tr>
              <?php} else if (strtolower($item["catagory"]) == "movies") { ?> 
          <tr>
                <th>Director</th>
                <td><?php echo $item["director"]; ?></td>
          </tr>
          <tr>
                <th>Writers</th>
                <td><?php echo implode(", ",$item["writers"]); ?></td>
          </tr>
          <tr>
                <th>Stars</th>
                <td><?php echo implode(", ",$item["stars"]); ?></td>
          </tr>
          <?php} else if (strtolower($item["catagory"]) == "music") { ?> 
          <tr>
                <th>Artist</th>
                <td><?php echo $item["artist"]; ?></td>
          </tr>
             <?php } ?>
        </table>


    </div>
  </div>


</div> ```

I have copied everything from each video regarding the details page. If someone could point to something that I may be overlooking, that would be great.